Elongated LED luminaire and associated methods

ABSTRACT

A fluorescent tube retrofit luminaire includes a lamp, a light guide, and a heat dissipating frame. The lamp may include a bi-pin base, middle structure, and outer structure, which may include a light-emitting diode (LED)-based light source in thermal communication with a finned heat sink section of the middle structure. Light emitted from the light source may be distributed generally along the length and/or width of the light guide. A bi-pin connector in the light guide may attach the luminaire to a first fluorescent socket. The bi-pin base may be received by a mounting aperture in the light guide before anchoring the luminaire to a second fluorescent socket using a pin-lock. The heat dissipating frame may be in thermal communication with both the light guide and the heat sink section of the lamp.

RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(e) of U.S.Provisional Patent Application Ser. No. 61/709,325 filed on Oct. 3, 2012and titled Elongated LED Lighting System and Associated Methods, theentire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to the field of lighting and, inparticular, to luminaires used to replace fluorescent lamps, andassociated methods.

BACKGROUND OF THE INVENTION

A fluorescent lamp (also called a fluorescent tube) uses electricalcurrent to excite a vapor within a glass tube resulting in the dischargeof electrons. Visible light is produced when the electrons cause amaterial coating the inner wall of the glass tube to fluoresce. Linearfluorescent lamps are routinely used in commercial or institutionalbuildings, and are commonly installed in troffer light fixtures(recessed troughs installed in a ceiling) and pendant light fixtures(housings suspended from a ceiling by a chain or pipe).

Fluorescent lamps have been steadily replacing incandescent lamps inmany lighting applications. Compared to an incandescent lamp, afluorescent lamp converts electrical power into useful light moreefficiently, delivers a significantly longer useful life, and presents amore diffuse and physically larger light source. However, fluorescentlamp technology has disadvantages. A fluorescent lamp is typically moreexpensive to install and operate than an incandescent lamp because thefluorescent lamp requires a ballast to regulate the electrical current.Fluorescent light fixtures cannot be connected directly to dimmerswitches intended for incandescent lamps, but instead require acompatible dimming ballast. The performance of fluorescent lamps may benegatively impacted by environmental conditions such as frequentswitching and operating temperatures. Many fluorescent lamps have poorcolor temperature, resulting in a less aesthetically pleasing light.Some fluorescent lamps are characterized by prolonged warm-up times,requiring up to three minutes before maximum light output is achieved.Also, if a fluorescent lamp that uses mercury vapor is broken, a smallamount of mercury (classified as hazardous waste) can contaminate thesurrounding environment.

Digital lighting technologies such as light-emitting diodes (LEDs) offersignificant advantages over traditional linear fluorescent lamps. Theseinclude, but are not limited to, better lighting quality, longeroperating life, and lower energy consumption. Increasingly, LEDs arebeing designed to have desirable color temperatures. Moreover, LEDs donot contain mercury. Consequently, a market exists for LED-basedretrofit alternatives to legacy lighting fixtures that use fluorescentlamps. However, a number of installation challenges and costs areassociated with replacing linear fluorescent lamps with LED illuminationdevices. The challenges, which are understood by those skilled in theart, include light production, thermal management, and installationease. The costs, which are similarly understood by those skilled in theart, typically stem from a need to replace or reconfigure a troffer orpendant fixture that is configured to support fluorescent lamps toinstead support LEDs.

By the very nature of their design and operation, LEDs have adirectional light output. Consequently, employing LEDs to produce lightdistribution properties approximating or equaling the light dispersionproperties of traditional lamps may require the costly andlabor-intensive replacement or reconfiguration of the host lightfixture, and/or the expensive and complexity-introducing design ofLED-based solutions that minimize the installation impact to the hostlight fixture. Often material and manufacturing costs are lost in thistrade off.

Another challenge inherent to operating LEDs is heat. Thermal managementdescribes a system's ability to draw heat away from the LED, eitherpassively or actively. LEDs suffer damage and decreased performance whenoperating in high-heat environments. Moreover, when operating in aconfined environment, the heat generated by an LED and its attendingcircuitry itself can cause damage to the LED. Heat sinks are well knownin the art and have been effectively used to provide cooling capacity,thus maintaining an LED-based light bulb within a desirable operatingtemperature. However, heat sinks can sometimes negatively impact thelight distribution properties of the light fixture, resulting innon-uniform distribution of light about the fixture. Heat sink designsalso may add to the weight and/or profile of an illumination device,thereby complicating installation, and also may limit available spacefor other components needed for delivering light.

Replacement of legacy lighting solutions may be complicated by the needto adapt LED-based devices to meet legacy form standards. For example,in a commercial lighting system retrofit, disposal of a replacedfluorescent lamp's fixture housing often is impractical. Consequently,retrofit lamps often are designed to adapt to a legacy fluorescentfixture, both functionally and aesthetically. Also, power supplyrequirements of LED-based lighting systems can complicate installationof LEDs as a retrofit to existing light fixtures. LEDs are low-voltagelight sources that require constant DC voltage or current to operateoptimally, and therefore must be carefully regulated. Too little currentand voltage may result in little or no light. Too much current andvoltage can damage the light-emitting junction of the LED. LEDs arecommonly supplemented with individual power adapters to convert AC powerto the proper DC voltage, and to regulate the current flowing throughduring operation to protect the LEDs from line-voltage fluctuations. Thelighting industry is experiencing advancements in LED applications, someof which may be pertinent to certain aspects of replacing linearfluorescent lamps.

U.S. Pat. No. 6,739,734 to Hulgan discloses a method of retrofitting afluorescent light fixture (e.g., four foot T12 or T8 lamps) withLED-based luminaires without requiring removal of the fixture housing.However, rather than maintain existing circuitry, the fixture isstripped not only of its fluorescent lamps but also of its wireway coverand ballast(s). U.S. Published Patent Application No. 2010/0033095 bySadwick discloses an apparatus for replacing a fluorescent lamp thatincludes an electrical connector adapted to maintain the existingcircuitry of the fixture, including the fluorescent ballast. A voltageconverter, direct current (DC) rectifier, and LED light source includedin the apparatus simulate the behavior of a fluorescent lamp in responseto signals from the fixture's existing circuitry. However, the referencedefines a lamp housing physically configured as a prosthetic replacementfor a fluorescent lamp in the fixture, rather than as a less expensivenon-tubular light-directing structure.

U.S. Pat. No. 6,936,968 to Cross et al., U.S. Pat. No. 6,997,576 toLodhie, and U.S. Published Patent Application No. 2012/0147597 by Farmerand all disclose versions of an LED light tube adapted for use introffer light fixtures. The Cross reference defines a cylindricalelongated transparent envelope holding at least one serial string ofLEDs along its length. Similarly, the Lodhie reference discloses asubstantially transparent hollow cylinder containing multiple LEDsarranged to form two LED arrays, and mounted along opposite sides of asubstantially planar printed circuit board (PCB). The Farmer referencealso defines a tubular structure, but employs one or more side lightLEDs combined with gradient optics to achieve a selected emitted lightintensity variation across the surface of the tube. Once again, allthree references define a lamp housing physically configured as aprosthetic replacement for a fluorescent lamp in the fixture, ratherthan as a less expensive non-tubular light-directing structure.

Accordingly, and with the above in mind, a need exists for an effectiveand inexpensive fluorescent lamp replacement. More specifically, a needexists for a fluorescent lamp replacement that may be employed withminimal reconfiguration of the existing troffer or pendant light fixturethat supported the replaced lamp. A fluorescent lamp replacement isneeded that may be manufactured at less cost than conventional retrofitlamps. Furthermore, a need exists for a fluorescent lamp that meets orexceeds the performance characteristics of fluorescent lamps, but alsodelivers the advantages of digital lighting technology (e.g., energyefficiency, tailorable color temperatures).

This background information is provided to reveal information believedby the applicant to be of possible relevance to the present invention.No admission is necessarily intended, nor should be construed, that anyof the preceding information constitutes prior art against the presentinvention.

SUMMARY OF THE INVENTION

With the above in mind, embodiments of the present invention are relatedto a luminaire adapted to be carried by a lighting fixture. Theluminaire may be configured as a retrofit to engage mechanically andoperationally with a conventional fluorescent light fixture. Theluminaire may advantageously offer a simple and inexpensive retrofitoption in terms of manufacturing, installation and maintenance. Thedesign of the luminaire may deliver performance (e.g., brightness) thatmeets or exceeds the characteristics of a replaced fluorescent lamp,while avoiding the material waste inherent to prosthetic tube retrofitdesigns. The use of digital lighting technology, such as LEDs, inconnection with the luminaire may advantageously provide decreasedoperating costs with respect to energy consumption. The LED-basedtechnology may support tailoring of color temperature in ways notpossible with standard fluorescent bulbs (e.g., color temperatures of3000 Kelvin and below). The on-board power conditioning for LED-basedlamps may provide for operation of the present invention using existingfluorescent light assembly circuitry and without requiring removal offluorescent ballasts.

The luminaire may comprise a lamp, a light guide, and a heat dissipatingframe. The lamp according to embodiments of the present invention mayinclude a bi-pin base, a middle structure connected to the bi-pin base,and an outer structure connected to the middle structure. The outerstructure may carry a light source such as a light-emitting diode (LED)that emits a source light. The middle structure may comprise asubstantially cylinder-shaped heat sink section in thermal communicationwith the light source. A plurality of fins may project radially outwardfrom the heat sink section such that at least a distal edge of each ofthe fins is substantially exposed to an environment external to theluminaire. The bi-pin base may comprise a pin lock configured to anchorthe lamp to a standard fluorescent socket.

A proximal side of the heat sink section may be positioned adjacent to ahousing section of the middle structure. A power supply may be carriedwithin an interior of the housing section. The power supply may beconfigured to convert and condition AC power to DC power for delivery tothe light source. The outer structure of the lamp also may comprise ashelf and an optic. The light source may be disposed on the shelf andoriented such that the source light emitted from the light source passesthrough the optic.

The light source may be configured to emit the source light incidentupon an inner surface of the light guide. Materials present in the lightguide may use collimation, concentration, refraction, conversion,reflection, and/or diffusion to change the source light into a shapedlight. The shaped light may illuminate a space proximate to theluminaire in a generally even distribution along the length and/or widthof the light guide. The light guide may have a bi-pin connectorconfigured to mechanically attach to a standard fluorescent socket. Amounting aperture may be positioned opposite the bi-pin connector on thesubstantially elongated-basket shaped light guide. The mounting aperturemay be sized to fittedly receive at least one of the bi-pin base and themiddle structure of the lamp. A portion of the outer structure of thelamp may be positioned adjacent to the light guide in the assembledluminaire.

A contact surface on the heat dissipating frame may be in thermalcommunication with an outer surface of the light guide. The contactsurface of the heat dissipating frame may comprise heat sink rodspositioned to abut each other. A through-hole may be positioned on asubstantially frustoconical attaching end of the heat dissipating frame.A rim of the through-hole may be in thermal communication with the heatsink section of the middle structure of the lamp.

A method aspect of the present invention is directed to assembling aluminaire as a retrofit for a fluorescent tube lamp. The method maycomprise the steps of removing the fluorescent tube lamp from afluorescent light fixture, positioning the heat dissipating frame inthermal contact with the light guide, aligning the through-hole in theheat dissipating frame with a mounting aperture in the light guide,inserting the bi-pin base and the middle structure of the lamp throughthe mounting aperture in light guide and, in turn, through thethrough-hole of the heat dissipating frame such that outer structure ofthe lamp is fixedly attached to the light guide adjacent the mountingaperture. The method also may include attaching the bi-pin connector ofthe light guide to the first fluorescent socket, and mechanically andelectrically attaching the pin lock of the bi-pin base to the secondfluorescent socket. The method also may include positioning the lightguide in relation to the light source such that the emitted source lightis incident upon the light guide, and is changed by the light guide intothe shaped light that illuminates the space proximate to the luminaire.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an assembled, perspective bottom view of an elongate LEDluminaire used in connection with a troffer fixture according to anembodiment of the present invention.

FIG. 1B is a first exploded perspective view of the elongate LEDluminaire illustrated in FIG. 1A.

FIG. 1C is a second exploded perspective view of the elongate LEDluminaire illustrated in FIG. 1A.

FIG. 2A is a side elevation view of a lamp of the elongate LED luminaireillustrated in FIG. 1A.

FIG. 2B is a front elevation view of the lamp illustrated in FIG. 2A.

FIG. 3A is a side perspective view of a light guide of the elongate LEDluminaire illustrated in FIG. 1A.

FIG. 3B is a top plan view of the light guide illustrated in FIG. 3A.

FIG. 3C is a cross-sectional view of the light guide illustrated in FIG.3A and taken through line 3-3 in FIG. 3B.

FIG. 4A is a side elevation view of a heat dissipating frame of theelongate LED luminaire illustrated in FIG. 1A.

FIG. 4B is a top plan view of the heat dissipating frame illustrated inFIG. 4A.

FIG. 4C is a cross-sectional view of the heat dissipating frameillustrated in FIG. 4A and taken through line 4-4 in FIG. 4B.

FIG. 5 is a flow chart detailing a method of retrofitting a fluorescenttube lamp with an elongate LED luminaire according to an embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Those ofordinary skill in the art realize that the following descriptions of theembodiments of the present invention are illustrative and are notintended to be limiting in any way. Other embodiments of the presentinvention will readily suggest themselves to such skilled persons havingthe benefit of this disclosure.

Although the following detailed description contains many specifics forthe purposes of illustration, anyone of ordinary skill in the art willappreciate that many variations and alterations to the following detailsare within the scope of the invention. Accordingly, the followingembodiments of the invention are set forth without any loss ofgenerality to, and without imposing limitations upon, the claimedinvention.

In this detailed description of the present invention, a person skilledin the art should note that directional terms, such as “above,” “below,”“upper,” “lower,” and other like terms are used for the convenience ofthe reader in reference to the drawings. Also, a person skilled in theart should notice this description may contain other terminology toconvey position, orientation, and direction without departing from theprinciples of the present invention. Like numbers refer to like elementsthroughout.

The terms “generally” and “substantially” may be used throughout theapplication. “Generally” may be understood to mean approximately, about,or otherwise similar in content or value. “Substantially” may beunderstood to mean mostly, more than not, or approximately greater thanhalf. The meanings of these terms must be interpreted in light of thecontext in which they are used, with additional meanings beingpotentially discernible therefrom.

Referring now to FIGS. 1A-5, a luminaire 100 according to an embodimentof the present invention is now described in detail. Throughout thisdisclosure, the present invention may be referred to as the luminaire100, a lighting system, a digital light, an LED lighting system, adevice, a system, a product, and a method. Furthermore, in the followingdisclosure, the present invention may be referred to as relating toreplacement of linear fluorescent lamps, fluorescent tube lamps, tubelights, troffer tubes, and fluorescent light bulbs. Those skilled in theart will appreciate that this terminology is only illustrative and doesnot affect the scope of the invention. For instance, the presentinvention may just as easily relate to lasers or other digital lightingtechnologies, and may operate as a retrofit for non-linear troffer tubesor to other fluorescent light configurations.

Example devices, systems, and methods for an elongate LED luminaire aredescribed herein below. In the following description, for purposes ofexplanation, numerous specific details are set forth to provide athorough understanding of example embodiments. It will be evident,however, to one of ordinary skill in the art that the present inventionmay be practiced without these specific details and/or with differentcombinations of the details than are given here. Thus, specificembodiments are given for the purpose of simplified explanation and notlimitation.

Referring now to FIGS. 1A, 1B, and 1C, an elongate LED luminaire 100configured to be carried by a light fixture will now be discussed. Invarious implementations, the luminaire 100 shown as part of a lightingassembly 102 in FIG. 1A and also shown separately as a luminaire 100 inFIGS. 1B and 1C may be used alone or together with other similarlighting assemblies in a system of lighting assemblies. For example, andwithout limitation, the luminaire 100 may be configured as a retrofit toengage mechanically and operationally with a conventional fluorescentlight fixture such as the light fixture 104 illustrated in FIGS. 1A-1C.Used alone or in combination with other lighting assemblies, theluminaire 100 may be advantageously employed as a fluorescent tubereplacement in a variety of applications including, but not limited to,direct-view or indirect-view interior or exterior space (e.g.,architectural) lighting and illumination in general. The luminaire 100may also be advantageously used in connection with direct or indirectillumination of objects or spaces, theatrical or otherentertainment-based/special effects lighting, decorative lighting,safety-oriented lighting, lighting associated with, or illumination of,displays and/or merchandise (e.g. for advertising and/or inretail/consumer environments), combined lighting or illumination andcommunication systems, as well as for various indication, display andinformation purposes.

More specifically, the luminaire 100, according to an embodiment of thepresent invention, may include a lamp 110, a light guide 140 positionedin optical communication with the lamp 110, and a heat dissipating frame170 positioned in thermal communication with at least one of the lamp110 and the light guide 140. Additionally, the luminaire 100 may furtherinclude one or more mounting brackets 179 adapted to mechanically attachthe luminaire 100 to a light fixture 104. Although luminaire 100 isdepicted as having an elongated basket shape in FIGS. 1A-1C, luminaire100 and its constituent components may have any of a variety of othershapes, including planar and cylindrical.

Referring additionally to FIGS. 2A and 2B, the lamp 110, according to anembodiment of the present invention, may include a bi-pin base 112, amiddle structure 120 connected to the bi-pin base 112, and an outerstructure 130 connected to the middle structure 120. The outer structure130 may be attached to the middle structure 120 which, in turn, may besimilarly connected to the bi-pin base 112 by any means known in theart, including, not by limitation, use of one or more of adhesives orglues, welding, and fasteners. In defining the middle structure 120 andouter structure 130, reference is made herein specifically to FIGS. 2,8, 9A, 9B, and 11, and the written description thereof, of U.S. patentapplication Ser. No. 12/698,829 titled Luminaire With Prismatic Opticfiled on May 3, 2012, the entire content of which is incorporated hereinby reference.

Continuing to refer to FIGS. 1A, 1B, 1C, and 2A, the bi-pin base 112 maybe configured to anchor to a fluorescent socket 106. More specifically,the bi-pin base 112 may be configured to mechanically and electricallycouple the lamp 110 to any standard fluorescent socket of a type that iswell known in the art, including, but not limited to, medium bi-pinsockets (T8/T12), mini bi-pin sockets (T5/T5HO), single pin sockets(T12/T8), and U-bend medium bi-pin sockets. Additionally, the lamp 110may be configured to conform to various sizes and configurations of theaforementioned sockets, including, but not limited to, turn-typesockets, pedestal sockets, and fixed-end sockets. For example, andwithout limitation, the bi-pin base 112 may include pin locks 114designed to engage the fluorescent socket 106 from within thefluorescent socket pin contacts, rather than relying on pressure appliedfrom outside the socket pin contacts to keep the lamp 110 fromdisengaging from the socket pin contacts due to minimal forces, such asgravity. Also for example, and without limitation, the bi-pin base 112may be formed of an electrically conductive material, such as copperand/or aluminum.

Referring again to FIGS. 2A and 2B, the middle structure 120 of the lamp110 may be configured to include a housing section 122 and a heat sinksection 124. In the present embodiment, the heat sink section 124 may beformed of thermally conductive material and may be positioned in thermalcommunication with a light source 255. Materials of the heat sinksection 124 may include, without limitation, thermoplastic, ceramics,porcelain, aluminum, aluminum alloys, metals, metal alloys, carbonallotropes, and composite materials. A portion of the heat sink section124 may include a plurality of fins 202. For example, and withoutlimitation, the fins 202 may be configured to run the length of the heatsink section 124 and may extend radially outward therefrom such that atleast a distal edge of the fins 202 are substantially exposed to anenvironment external to the luminaire. The fins 202 may increase thesurface area of the heat sink section 124 and may permit fluid flowbetween adjacent pairs of fins 202, thereby enhancing the coolingcapability of the heat sink section 124. Additional information directedto the use of heat sinks for dissipating heat in an illuminationapparatus is found in U.S. Pat. No. 7,922,356 titled IlluminationApparatus for Conducting and Dissipating Heat from a Light Source, andin U.S. Pat. No. 7,824,075 titled Method and Apparatus for Cooling aLight Bulb, the entire contents of each of which are incorporated hereinby reference.

Continuing to refer to FIG. 2A, a proximal side of thesubstantially-cylindrical heat sink section 124 may be positionedadjacent to a distal side of the substantially-cylindrical housingsection 122 of the middle structure 120. For example, and withoutlimitation, each of the heat sink section 124 and the housing section122 of the middle structure 120 shown in FIG. 2A may include a void suchthat the two voids cooperate with each other to define a longitudinalcavity (see also 208 in FIG. 2 of U.S. patent application Ser. No.12/698,829 which is incorporated herein by reference). Electricalcircuitry may be configured to be substantially enclosed within themiddle structure 120 according to an embodiment of the invention. Forexample, and without limitation, a power source (not shown) may beconfigured to have a shape and sufficient dimensions to be disposedwithin the longitudinal cavity 208 of the middle structure 120.

The power supply may be configured to convert and condition AC power toDC power for delivery to the light source 225. In one embodiment, thebi-pin base 112 may conduct power from a light fixture that may provide120-volt alternating current (AC) power. Furthermore, in the embodiment,the light source 225 may comprise LEDs 227 requiring direct current (DC)power at, for instance, five (5) volts. Accordingly, the power supplymay comprise circuitry for conditioning the 120-volt AC power to 5-voltDC power. The characteristics of the power being provided to the powersupply and be provided by the power supply are exemplary only, and awide range of characteristics of electricity are contemplated includedwithin the scope of the invention. For example, the bi-pin base 112 mayconduct power from a light fixture that may provide power having avoltage within the range of from about 110 votes to about 250 V and afrequency within the range from about 40 Hz to about 70 Hz. Detailsregarding power supply systems that may be used in connection with theluminaire 100 according to an embodiment of the present invention may befound, for example, in U.S. Provisional Patent Application No.61/486,322 titled Variable Load Power Supply, the entire content ofwhich is incorporated herein by reference.

Continuing to refer to FIGS. 2A and 2B, according to an embodiment ofthe present invention, the outer structure 130 may include a shelf 210,an optic 220, and one or more light sources (225). The outer structure130 may be configured to permit the one or more light sources 225 to bedisposed therein and positioned to direct light through the optic 220.In the present embodiment, the shelf 210 may be disposed about aperimeter of the outer structure 130 adjacent the interface between theouter structure 130 and the middle structure 120.

Each light source 225 carried by the outer structure 130 may be providedas one of any number of embodiments. For example, and withoutlimitation, any one of the light sources 225 may include light emittingelements 227. The light emitting elements 227 that may be included inthe outer structure 130 may include one or more light-emitting diodes(LEDs) 227. It should be appreciated by the skilled artisan that thelock lamp 110 illustrated in FIG. 2B may include any number of varioustypes of light sources (e.g., all LED-based light sources, LED-based andnon-LED-based light sources in combination, etc.) adapted to generateradiation of a variety of different colors, including essentially whitelight, as will be discussed further below. More specifically,embodiments of the present invention contemplate that any number oflight sources may be provided, in addition to any number of differentlight sources.

Each light source 225 may be configured to emit a source light, whichmay be defined as a combination of the emissions of each light source225 present in the lamp 110. Each light source 225 may be configuredsuch that the emitted source light may be incident upon an inner surface142 of the light guide 140 and subsequently projected generally radiallyoutward from the lamp 110. For example, and without limitation, thelight guide 140 may be configured to alter the source light to create ashaped light having a uniform illuminance as projected into theenvironment exterior to the luminaire 100. One or more of the componentscomprising the luminaire 100 may be connected by any means or methodknown in the art, including, not by limitation, use of adhesives orglues, welding, interference fit, and fasteners. Alternatively, one ormore components of the luminaire 100 may be molded during manufacturingas an integral part of the luminaire 100.

Continuing to refer to FIGS. 2A and 2B, the outer structure 130 of thelamp 110 also may comprise a shelf 210 and an optic 220. The lightsource 225 may be disposed on the shelf 210 and oriented such that thesource light emitted from the light source 225 passes through the optic220. The optic 220 may be configured to direct the source light emittedfrom a light source 225 to be incident upon the light guide 140. Theoptic 220 may be formed of any transparent, translucent, orsubstantially translucent material including, but not limited to, glass,fluorite, and polymers, such as polycarbonate. Types of glass include,without limitation, fused quartz, soda-lime glass, lead glass, flintglass, fluoride glass, aluminosilicates, phosphate glass, borate glass,and chalcogenide glass.

Referring now to FIGS. 3A, 3B, and 3C, and additionally to FIGS. 1A, 1B,and 1C, the light guide 140 of the present embodiment of the luminaire100 may include an inner surface 142, an outer surface 144, a mountingaperture 146, and a bi-pin connector 148. The components comprising thelight guide 140 may be connected by any means known in the art,including, not by limitation, use of adhesives or glues, welding, andfasteners. Alternatively, one or more components of the light guide 140may be molded during manufacturing as an integral part of the lightguide 140.

As described above, a portion of the outer structure 130 of the lamp 110may be positioned adjacent to the light guide 140 in the assembledluminaire 100. More specifically, the light source 225 of the lamp 110may be configured to emit light incident upon the inner surface 142 ofthe light guide 140. Materials present in the light guide 140 may changethe source light into a shaped light using at least one of collimation,concentration, refraction, conversion, reflection, and/or diffusion. Forexample, and without limitation, the shaped light may illuminate a spaceproximate to the luminaire in a generally even distribution along thelength and/or width of the light guide 140.

As shown in FIGS. 1C, 3A and 3B, the light guide 140 may have a bi-pinconnector 148 configured to mechanically attach to a standardfluorescent socket 106. For example, and without limitation, the bi-pinconnector 148 may be configured to conform to a standard bi-pin socket106 for a fluorescent lampholder that is well known in the art. However,the light guide 140 may be configured to mechanically attach via thebi-pin connector 148 to any fluorescent socket 106, including, but notlimited to, medium bi-pin sockets (T8/T12), mini bi-pin sockets(T5/T5HO), single pin sockets (T12/T8), and U-bend medium bi-pinsockets. Additionally, the bi-pin connector 148 may be configured toconform to various sizes and configurations of the aforementionedsockets, including, but not limited to, turn-type sockets, pedestalsockets, and fixed-end sockets. The bi-pin connector 148 may be made ofa non-conductive material which may support mechanical attachment to thefluorescent socket 106, but which may not allow electrical current topass through the light guide 140. For example, and without limitation,the length of the bi-pin connector 148 may be long enough to providemechanical attachment to the fluorescent socket pin contacts, but notlong enough to engage the electrical connections within the socket pincontacts.

Continuing to refer to FIGS. 1C, 3A and 3B, the light guide 140 may havea substantially elongated-basket shape that defines an inner surface 142and an outer surface 144. The outer structure 130 of the lamp 110 may bepositioned adjacent to the inner surface 142 of the light guide 140 whenthe lamp 110 is received by the mounting aperture 146 of the light guide140. In some embodiments, the one or more light sources 225 in the outerstructure 130 of the lamp 110 may be arranged such that each pointssubstantially upwards towards a target reflective area on the innersurface 142 of the light guide 140. This configuration mayadvantageously enhance light dispersion as light is emitted from thelamp 110, resulting in an inexpensive way to distribute a light patternthat covers the entire target space proximate to the lighting system100.

For example, and without limitation, as illustrated in FIGS. 1C, 3A and3B, the mounting aperture 146 may be positioned on a substantiallyfrustoconical single end of the elongate-basket shaped light guide 140that may be opposite a second end to which the bi-pin connector 148 maybe connected. The mounting aperture 146 may be sized to fittedly receivelamp 110 such that the bi-pin connector 112 and the middle structure 120may pass through the mounting aperture 146, but the shelf 210 of theouter structure 130 of the lamp 110 may be too large to pass through themounting aperture 146.

The inner surface 142 may include one or more of any type of reflectivematerials which may be known in the art. For example, and withoutlimitation, the inner surface 142 may be formed of a material that isinherently reflective of light, and therefore a surface upon whichemitted light may be incident inherently would be reflective. As anotherexample, the inner surface 142 may be formed of a material that may bepolished to become reflective. As yet another example, the inner surface142 may be formed of a material that is permissive of a material beingcoated, attached, or otherwise disposed thereupon, the disposed materialbeing reflective. As yet another example, as illustrated in FIG. 3C, thelight guide 140 may comprise layers of transmissive 310 and reflective320 materials. Properties such as, and without limitation, the thicknessand the orientation of the transmissive 310 and reflective 320 materialsmay be manipulated to alter the intensity and direction of the shapedlight depending on the distance from a given reflective area on theinner surface 142 of the light guide 140 to the one or more lightsources 225 in the outer structure 130 of a lamp 110. As yet anotherexample, it is contemplated that a coating may be placed on the innersurface 142 of the light guide 140 to convert a wavelength of the sourcelight so that the wavelength is defined has having a convertedwavelength range. For additional disclosure regarding coatings used toconvert a wavelength of a source light, see U.S. patent application Ser.No. 13/234,371 titled Color Conversion Occlusion and Associated Methods,and U.S. patent application Ser. No. 13/357,283 titled DualCharacteristic Color Conversion Enclosure and Associated Methods, theentire contents of each of which are incorporated herein by reference.These methods of forming the light guide 140 are exemplary only and donot serve to limit the scope of the invention. All methods known in theart of forming the reflective inner surface 142 are contemplated andincluded within the scope of the invention.

Additionally, in some embodiments, the luminaire may be configured toconform to a U-bend florescent bulb configuration, such that theluminaire may be a legacy retrofit for such a troffer fixture. In suchembodiments, the light guide may be configured to redirect light suchthat light is emitted substantially equally throughout the light guide,including those sections of the light guide that are generally distal ofthe human relative to the light source. Aside from this characteristic,U-bend luminaire embodiments of the invention may be substantiallysimilar or identical to the linear embodiment presented herein,including all necessary and optional features described therewith, withthe exception of each feature that must be reconfigured to conform to aU-bend type troffer fixture.

Referring now to FIGS. 1A, 1B, 1C, 4A and 4B, the heat dissipating frame170 of the present embodiment of the lighting system 100 may include acontact surface 172, a mounting surface 174, and a through-hole 176. Forexample, and without limitation, the contact surface 172 on the heatdissipating frame 170 may be positioned in thermal communication withthe outer surface 144 of the light guide 140. The components comprisingthe heat dissipating frame 170 may be connected by any means known inthe art, including, not by limitation, use of adhesives or glues,welding, and fasteners. Alternatively, one or more components of theheat dissipating frame 170 may be molded during manufacturing as anintegral part of the heat dissipating frame 170. A rim of thethrough-hole 176 may be in thermal communication with the heat sinksection 124 of the middle structure 120 of the lamp 110.

Continuing to refer to FIG. 1C, the heat dissipating frame 170 of theluminaire 100 according to an embodiment of the present invention mayinclude one or more heat sink rods 173 that may abut each other todefine the contact surface 172 of the heat dissipating frame 170. Invarious implementations, the heat dissipating frame 170 may be made ofaluminum or other heat-conducting material by molding, casting, orstamping. A through-hole 176 may be disposed at a substantiallyfrustoconical attaching end of the heat dissipating frame 170. Thethrough-hole 176 may comprise a rim, defined as a perimeter of thethrough-hole 176, that may be sized to mechanically and thermally couplethe heat dissipating frame 170 to the heat sink section 124 of themiddle structure 120 of the luminaire 100 (illustrated in FIG. 2A). Forexample, and without limitation, in the luminaire 100 presented in anassembled position as illustrated in FIG. 1B, the through-hole 176 ofthe heat dissipating frame 170 may be aligned with the mounting aperture146 of the light guide 140 with the contact surface 172 of the heatdissipating frame 170 substantially adjacent to the outer surface 144 ofthe light guide 140. The lamp 110 may be received simultaneously by boththe mounting aperture 146 and the through-hole 176 before mechanicallyand electrically engaging the fluorescent socket 106 with its bi-pinbase 112. In such a configuration, the weight of the heat dissipatingframe 170 may be supported by the outer surface 144 of a light guide 140that is mechanically attached to opposing fluorescent sockets 106 by thebi-pin connector 148 and by the anchored lamp 110, respectively.Additionally, the mounting surface 174 of the heat dissipating frame 170may be mechanically attached to a lighting assembly 102 using brackets179 as illustrated in FIGS. 1B and 1C.

In various implementations of the present invention, the luminaire 100may be configured as a retrofit to engage mechanically and operationallywith a conventional fluorescent light fixture. The luminaire 100 shownin FIGS. 1A, 1B, and 1C is an advantageously simple and inexpensiveretrofit option in terms of manufacturing, installation and maintenance.For example, the design of the present invention avoids the materialwaste inherent to prosthetic tube retrofit designs. Furthermore, theon-board power conditioning for LED-based lighting provides foroperation of the present invention using existing fluorescent lightassembly circuitry and without requiring removal of fluorescentballasts. The use of LEDs in connection with the lighting system 100according to an embodiment of the present invention also advantageouslyprovides decreased operating costs with respect to energy consumption.Also, LED-based technology supports tailoring of color temperature inways not possible with standard fluorescent bulbs (e.g., colortemperatures of 3000 Kelvin and below). Additionally, LED-basedtechnology enables the adjustment of color temperature post-installationwithout requiring replacement of the bulb.

A method aspect of the present invention is directed to assembling aluminaire as a retrofit for a fluorescent tube lamp. The method maycomprise the steps of removing the fluorescent tube lamp from afluorescent light fixture, positioning the heat dissipating frame inthermal contact with the light guide, aligning the through-hole in theheat dissipating frame with a mounting aperture in the light guide,inserting the bi-pin base and the middle structure of the lamp throughthe mounting aperture in light guide and, in turn, through thethrough-hole of the heat dissipating frame such that outer structure ofthe lamp is fixedly attached to the light guide adjacent the mountingaperture. The method also may include attaching the bi-pin connector ofthe light guide to the first fluorescent socket, and mechanically andelectrically attaching the pin lock of the bi-pin base to the secondfluorescent socket. The method also may include positioning the lightguide in relation to the light source such that the emitted source lightis incident upon the light guide, and is changed by the light guide intothe shaped light that illuminates the space proximate to the luminaire.

Referring now to FIG. 5, and continuing to refer to FIGS. 1A, 1B, and1C, a method aspect 500 for retrofitting a fluorescent tube lamp with aluminaire 100 adapted to be carried by a lighting fixture 106 will nowbe discussed. From the start 505, the retrofit method 500 may includethe step of removing a legacy fluorescent lamp from the light fixture106 (Block 510). At Block 520 the heat dissipating frame 170 may bepositioned to be carried by the light guide 140. For example, andwithout limitation, the contact surface 172 of the heat dissipatingframe 170 also may be positioned in thermal communication with the outersurface 144 of the light guide 140. At Block 530, the through-hole 176of the heat dissipating frame 170 may be aligned with the mountingaperture 146 of the light guide 140 such that the lamp 110 may bereceived simultaneously by both the mounting aperture 146 and thethrough-hole 176. At Block 540, the bi-pin base 112 and the middlestructure 120 of the lamp 100 may be inserted through the mountingaperture 146 and the through-hole 176 such that the shelf 210 of theouter structure 130 of the lamp 110 abuts the light guide 140. Thebi-pin connector 148 of the light guide 140 may be mechanically attachedto a first fluorescent socket 106 at Block 550. The bi-pin base 112 ofthe lamp 110 may be mechanically and electrically attached to a secondfluorescent socket 106 at Block 560. In such a configuration, the weightof the heat dissipating frame 170 may be supported by the outer surface144 of the light guide 140 that is mechanically attached to opposingfluorescent sockets 106 by the bi-pin connector 148 and by the anchoredlamp 110, respectively. At Block 570, the light source 225 of the lamp110 may be configured to emit light incident upon the inner surface 142of the light guide 140 such that the light guide 140 may change thesource light into the shaped light that may illuminate the spaceproximate to the luminaire in a generally even distribution along thelength and/or width of the light guide 140. The process ends at Block575.

Some of the illustrative aspects of the present invention may beadvantageous in solving the problems herein described and other problemsnot discussed which are discoverable by a skilled artisan. While theabove description contains much specificity, these should not beconstrued as limitations on the scope of any embodiment, but asexemplifications of the presented embodiments thereof. Many otherramifications and variations are possible within the teachings of thevarious embodiments. While the invention has been described withreference to exemplary embodiments, it will be understood by thoseskilled in the art that various changes may be made and equivalents maybe substituted for elements thereof without departing from the scope ofthe invention. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the inventionwithout departing from the essential scope thereof. Therefore, it isintended that the invention not be limited to the particular embodimentdisclosed as the best or only mode contemplated for carrying out thisinvention, but that the invention will include all embodiments fallingwithin the scope of the appended claims. Also, in the drawings and thedescription, there have been disclosed exemplary embodiments of theinvention and, although specific terms may have been employed, they areunless otherwise stated used in a generic and descriptive sense only andnot for purposes of limitation, the scope of the invention therefore notbeing so limited. Moreover, the use of the terms first, second, etc. donot denote any order or importance, but rather the terms first, second,etc. are used to distinguish one element from another. Furthermore, theuse of the terms a, an, etc. do not denote a limitation of quantity, butrather denote the presence of at least one of the referenced item.

Many modifications and other embodiments of the invention will come tothe mind of one skilled in the art having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings. Thescope of the invention should be determined by the appended claims andtheir legal equivalents, and not by the examples given Therefore, it isunderstood that the invention is not to be limited to the specificembodiments disclosed.

That which is claimed is:
 1. A luminaire comprising: a lamp comprisingan outer structure, a light source configured to emit a source light andcarried by the outer structure, a middle structure connected to theouter structure and comprising a heat sink section in thermalcommunication with the light source, and a bi-pin base connected to themiddle structure; a light guide having an inner surface and an outersurface; and a heat dissipating frame having a contact surface inthermal communication with the outer surface of the light guide; whereinthe light source is configured to emit the source light so as to beincident upon the inner surface of the light guide; and wherein thelight guide is configured to change the source light into a shaped lightthat illuminates a space proximate to the luminaire.
 2. The luminaireaccording to claim 1 wherein the bi-pin base comprises a pin lockconfigured to anchor the lamp to a standard fluorescent socket.
 3. Theluminaire according to claim 1 wherein the light source comprises alight-emitting diode (LED).
 4. The luminaire according to claim 1wherein the outer structure of the lamp further comprises a shelf and anoptic; and wherein the light source is disposed on the shelf andoriented such that the source light emitted from the light source passesthrough the optic.
 5. The luminaire according to claim 1 wherein thelight guide is further configured to change the source light into theshaped light using at least one of collimation, concentration,refraction, conversion, reflection, and diffusion.
 6. The luminaireaccording to claim 1 wherein the inner surface of the light guidecomprises an optically transmissive material and a reflective materialthat are configured, in combination, to change the source light into theshaped light.
 7. The luminaire according to claim 1 wherein the lightguide comprises a conversion material configured to convert a wavelengthof the source light so that the wavelength of the shaped light isdefined as having a converted wavelength range.
 8. The luminaireaccording to claim 1 wherein the light guide comprises a bi-pinconnector configured to mechanically attach to a standard fluorescentsocket.
 9. The luminaire according to claim 8 wherein the light guidecomprises a mounting aperture positioned opposite the bi-pin connector;and wherein the mounting aperture is sized to fittedly receive at leastone of the bi-pin base and the middle structure of the lamp such that aportion of the outer structure of the lamp is positioned adjacent to thelight guide.
 10. The luminaire according to claim 9 wherein the lightguide comprises a substantially elongated-basket shape between thebi-pin connector and the mounting aperture.
 11. The luminaire accordingto claim 10 wherein the heat sink section is substantiallycylinder-shaped and comprises a plurality of fins configured to projectradially outward therefrom.
 12. The luminaire according to claim 11wherein the middle structure comprises a housing section configured toengage the heat sink section such that a proximal side of the heat sinksection is positioned adjacent to the exterior of the housing section,and a distal edge of each of the plurality of fins is substantiallyexposed to an environment external to the luminaire.
 13. The luminaireaccording to claim 12 further comprising a power supply that is carriedwithin the interior of the housing section, electrically coupled to thelight source, and configured to convert and condition AC power to DCpower.
 14. The luminaire according to claim 1 wherein the heatdissipating frame comprises a plurality of heat sink rods positioned toabut each other to define the contact surface of the heat dissipatingframe.
 15. The luminaire according to claim 1 wherein the heatdissipating frame comprises a through-hole positioned on a substantiallyfrustoconical attaching end of the heat dissipating frame.
 16. Theluminaire according to claim 15 wherein a rim of the through-hole is inthermal communication with the heat sink section of the middle structureof the luminaire.
 17. A luminaire comprising: a lamp comprising an outerstructure, a light source carried by the outer structure and comprisinga light-emitting diode (LED) configured to emit a source light, a middlestructure connected to the outer structure and comprising a heat sinksection in thermal communication with the light source, and a bi-pinbase connected to the middle structure and comprising a pin lockconfigured to anchor the lamp to a first fluorescent socket; a lightguide having an inner surface and an outer surface, and comprising abi-pin connector configured to mechanically attach to a secondfluorescent socket; and a heat dissipating frame having a contactsurface in thermal communication with the outer surface of the lightguide; wherein the light source is configured to emit the source lightso as to be incident upon the inner surface of the light guide; andwherein the light guide comprises an optically transmissive material anda reflective material that are configured, in combination, to change thesource light into a shaped light that illuminates a space proximate tothe luminaire in a generally even distribution along at least one of alength of the light guide and a width of the light guide.
 18. Theluminaire according to claim 17 wherein the light guide comprises amounting aperture positioned opposite the bi-pin connector; and whereinthe mounting aperture is sized to fittedly receive the bi-pin base andthe middle structure of the lamp such that a portion of the outerstructure of the lamp is positioned adjacent to the light guide.
 19. Theluminaire according to claim 17 wherein the heat dissipating framecomprises a through-hole disposed on an attaching end of the heatdissipating frame and positioned such that a rim of the through-hole isin thermal communication with the heat sink section of the middlestructure of the luminaire.
 20. A method for retrofitting a fluorescenttube lamp with a luminaire that includes a lamp comprising an outerstructure comprising a light source configured to emit a source light, amiddle structure attached to the outer structure, and a bi-pin baseattached to the middle structure, the luminaire further including alight guide and a heat dissipating frame, the method comprising:removing the fluorescent tube lamp from a fluorescent light fixturecomprising first and second fluorescent sockets; positioning a contactsurface of the heat dissipating frame substantially adjacent to and inthermal contact with an outer surface of the light guide; aligning athrough-hole in the heat dissipating frame with a mounting aperture inthe light guide; inserting the bi-pin base and the middle structure ofthe lamp through the mounting aperture in the light guide and, in turn,through the through-hole of the heat dissipating frame such that theouter structure of the lamp is fixedly attached to the light guideadjacent the mounting aperture; mechanically attaching a bi-pinconnector disposed on a first end of the light guide to the firstfluorescent socket; anchoring the lamp to the second fluorescent socketby mechanically and electrically attaching to the second fluorescentsocket at least one pin lock disposed on the bi-pin base; andpositioning the light guide in relation to the light source such thatthe source light emitted from the light source is incident upon an innersurface of the light guide, and is changed by the light guide into ashaped light that illuminates a space proximate to the luminaire.